Electrical contact device.



C. P. JENKINS. ELECTRICAL CONTACT DEVICE.

APPLICATION FILED AUG.21,1908.

Patented Dec. 7, 1909.

Witness w n m a CHARLES FRANCIS JENKINS, OF WASHINGTON, DISTRICT COLUMBIA.

ELECTRICAL EONTACT DEVICE.

Specification of Letters latent.

Patcnted'Dcc. Y, 1909 lpplication filed August 21, 1908. Serial No. 449,683.

all whom it my mom:

it known that 1, CHARLES FnANois Jnivrsttns, citizen of the nited States, residing at Washington, in the District of Columbia, have invented certain new and useful Im rovements in Electrical Contact Devices, 0 which the following is a specification, reference being had therein to the accompanying drawing. Y

This invention relates to electrical contact devices for instantaneously making and again breaking circuits and it is shown for illustration as embodied in apparatus for use in connection with the igniters of a four cylinder internal combustion-engine. In de vices of the same class, it is common to to tate a contact picceslowly' over fixed contact pieces successively, to actuate the several igniters at proper intervals. Such devices maintain closed circuits during a large fraction of the entire time that the engine is in operation, making it necessary to replace the battery cells frequently, which often leads to much vexation.

The object of this invention is to eliminate these evils without introducing others. This end is attained by delaying the advance of the movin contact piece during the time that it is etween successive fixed contacts and then allowing a spring to throw it suddenly over the surface of the fixed contact piece.

In the accompanying drawings, Figure 1 is a perspective view of the apparatus with the cover of its casing removed. Fig. 2 is an axial. section of the devices shown in Fig. 1, the cover being in place.

In these views, A represents a cup-shaped casing provided with a cover A and having in its bottom a central opening for a rotary shaft B electrically connected with a battery or the like and rotated in the usual way, all as in well known devices of the same general class. lVithin this case and equally spaced around its marginal portion are four fixed spring contact pieces C, insulated from the case and shaft and each provided with a conductor C leading to the corresponding igniter, not shown. Within the case, also, ajplate D isfixcd to the shaft, and upon this is centrally pivoted a conducting bar E the outer end of which serves as a moving contact piecenormally in position to sweep under the fixed contacts successively, as the shaft rotates. The bar is held in radial position by a helical spring E attached to its inner end, normally al-ining with it, and having its own opposite end secured to the plate I). Between successive fixed contact pieces and near the outer wall of the casing is secured a mass of rigid insulatin material having internal faces F forwar ly-and inwardly inclined in the norniaipath of the outer end of the ivoted bar the inner end of each face a minating, near the corresponding fixed contact piece, at an abrupt offset 111 the insulating material.

In operation, the fixed and the moving contact pieces are connected with the terminals, respectively, of a. battery which in cludes the igniters in circuit, and the shaft is slowly rotated, all in the usual way. As the shaft rotates,the contact piece E moves with it untilthe outer end of the bar strikes one of the inclined surfaces which cause the bar to swing upon its pivot, as shown in Fig. l, the spring extending to'permit such movement. When the rearwardly swung outer end of the bar passes from the inclined surface, the recoilof the spring throws the bar inslantly'to normal position upon the opposite side of the fixed contact piece, and during" this instant, contact is made and again broken precisely as it would have been made and broken if the moving contact had been fixed to the shaft, except that the contact is of hardly appreciable. duration. The contact is thus made with all the certainty of the slow cont-act but the battery energy consumed is. very greatly lessened combination with a contact piece mounted to move in a predetermined path and to be moved from its normalposition, during advance, by retarding or accelerating its movement, of a series of contact pieces fixed a. intervals in said path, means for retarding and suddenly releasing the moving contact piece as it approaches each fixed contact piece, and a spring yieldingly resisting both the retardation and the counter movement beyond normal position.

2. The combination with a series of fixed contact pieces, of a co-acting contact bar mounted to approach each of the fixed pieces in succession and pivoted to swing freely forward and rearward from its normal alinement during such approach, means for retarding and suddenly releasing the bar as it approaches each fixed piece and a spring arranged to resist both retardation and the movement of the bar forward past its normal position when released.

3. The combination With a series of contact pieces mounted in a circle, of a traveling contact piece mounted to move around the circle making contact with the fixed pieces in succession and to be moved from its normal position, during advance, by retarding or accelerating its movement, spring devices permitting- While resisting both retardation and the opposite movement beyond normal position, and means for retarding and suddenly releasing the traveling contact piece as it approaches each of the other contact pieces.

of a centrally and freely pivoted laterally extending contact piece carried by the shaft a series of contact pieces arranged in the path of the outer end of the pivoted contact piece, an alin'ing spring connected to the opposite end of the pivoted piece and adapted to resist its swinging in either direction on its pivot, and means for retarding and suddenly releasing the outer end of the pivoted piece as it approaches each of the other pieces.

In testimony whereof I afiix my signature in presence of tWo Witnesses.

CHARLES FRANCIS JE Witnesses FRANCIS S'li literirnn, VVALLAoE GREENE. 

